Method of making drums



Nov; 25, 1930. w. A. JONES 1,782,899

METHOD OF MAKING DRUMS Filed March 19, 1926 2 Sheets-Shet 1 Fig! I/VVENTOR m/MQ Nov. 25, 1930. w! JONES 1,782,899

METHOD OF MAKING DRUMS Filed March 19,1926 2 Sheets-Sheet 2 I of A ayii/izvrole BY A TTORNE Y5 Patented Nov. 25, 1930 UNITED STATE-S:

"PATENT. oF ic WILLIAM A. JONES, or wEs'r nEw BRIGHTON, New YORK, AssIenon TO THE Ban coox & wILoox oomramr, or BAYONNE, NEW JERSEY, a CORPORATION or NEW JERSEY mi'rnon or mme m nus Application, filed March 19, 1926. Serial No. 96,110.

My-invention'will be best understood from the following description, and the annexed drawing,in which Fig. 1 is a lon itudinal section of an illustrativeform of rum em- 5 bodying my invention; Fig.2 is a section on' cordance with mymet-hod.

indicate like .of the drum (though such a manhole at one end only will sometimes be suflicient), this manhole being closed, in the illustrative form, by a known form of manhole cover 12 seated against a gasket seat 13 which, in the illustrative form, iscircular and is machined on the interior of the-drum head. The cover 12.is held in lace in the usual manner by bolts 14 exten ing throu h straps-15 extending across the exterior o the manhole. The particular form of manhole cover is no part of my present invention and further descri t1on thereof will be unnecessary to those skil ed in the art. If the drum lO'is used as a boiler drum, tubes, such as 16 and 17, will enter the i cylindrical portion of the drum'in the usual manner, one form of which is shown in Figs. 1 and 2.

Preferably, in forming the drum, I first provide a cylindrical shell with its walls of substantially uniform thickness throughout its length and then force the end of this shell inward toward the axis of theshell and,'at. the same time, toward the opposite end of the shell. In other words, the end 18 of the shell is carried-inward approximately along the curved line 19 to t o full-lineposition 1n Fig. 3, with the metal ori 'nally at the point 18, positioned atabout t e point 20 at the 'periphery'of the desired manhole o emng. The metal in the cylindrical wall is cut, in effect, around a point, such as 20 or 21, of the shell 10. 1

By-forcing the metal inward and lon 't'udinally of the drum in this manner, it is o vious that the metal .of the drum head being formed will be increased in cross-section in accordance with the distance toward the axis of the .drum to which any particular part of the shell 10 is moved, since the sectionmust make up in thickness what it is losing in circumference. It will also be obvious that the head will have a* continuous convex curvature, which is more desirable than the part1 convex and partly concave curves hereto ore found in drums of this sort. I

The metal may be forced into the full-line position of Fig. 3 in several ways, but preferably'I do this by a series of blows, as with a steam hammer, the drum being rotated between the blows, so that the net result is a series of blows a plied to the end 18 of the shell and successive y around it, such blows being struck in directions at an angle to the cylinder axis and toward the opposite end of the shell.

I have indicated on the drawings in dotted line positions 18" and 18", the general shape that the drum head of the illustrative embodiment will occupy as it is being forced into its final position. It should be understood, how- .ever, that, instead of this series of blows, the:

.metal may be forced into its final position by a hfydraulic press or by rolls. After the drum is position required to get the desired diameter of hole, the cover seat 13 is formed on the inside of the drum to receive the cover 12.

Preferably, I form the drum headinto a hemispherical shape, though such shape may, if desired, be more'or less conical, any surface of revolution having its curves all convex givmg some of the advantages of my invention, provided it is such that. in forming it, the metal of the shell wall assumes a section in which the thickness of the metal gradually increases from that of the. shell wallto a maximum at the periphery of the manhole opening.

In a shell formedin the manner described orced inwardly and longitudinally to the above, when internal pressure is applied, the' unit stresses in the metal adjacent the'man- 1 hole opening are substantially the same as those in the cylindrical portion of the shell 10 when internal pressure is applied to the drum. With the proportions shown in the drawing, the strength of the hemispherical head throughout and particularly at the edges of the opening, is actually greater than the strength of the c lindrical shell.

While preferahlythe drum. head will be formed directly on the end of a long cylindrical shell so as to make a seamless drum, it is obvious that my method may beapplied to the making of drum heads wh1ch would thenbe riveted into cylindrical drum shells or other wise attached to them.

"I claim:

1. The method of forming a continuous walled drum'having a hole in one end thereof which comprises forminga shell with a wall of uniform thickness, forcing the end of the shell inwardly toward the axis of the shell until the end edge of the shell reaches the diameter of said hole, thickening the shell around said hole by forcing said end of the shell toward the opposite end thereof, and forming a cover seat around the hole inside the drum.

- 2. The method of forming a continuous walled drum having a holein one end thereof which comprises forming a shell with a wall of uniform thickness, forcing the-end of the shell inwardly toward the axis of the shell until the end edge of the shell reaches the diameter of said hole, simultaneously thickening the shell around said hole by forcing said end of the shell toward the opposite end thereof, and forming a cover seat around the hole inside the drum.

3. The method of forming a continuous walled drum having a hole in one end thereof which comprises forming a cylindrical shell with a wall of uniform thickness, forcing the end of the shell inwardly toward the axis of the shell until the end edge of the shell reaches the diameter of said hole, simultaneously thickening the shell around said hole by forcing said end of the shell toward the opposite end thereof, shaping the end of the drum into 1 side the drum.

an externally convex surface of revolution, and forming a cover seat around the hole 1n- WILLIAM A. JONES. 

